1. Field of the Invention
The invention relates to a crystal device, wherein a bonding status of an electrically-conductive adhesive agent can be inspected, and an inspection method of the crystal device.
2. Description of the Related Art
It is known that a crystal device is formed by forming excitation electrodes and electrode pads on a crystal plate, and electrically connecting the electrode pads with a package via an electrically-conductive adhesive agent. In such a crystal device, the bonding status of the electrically-conductive adhesive agent and the electrode pads affects the characteristics of the crystal device. For example, if a bonding area of the electrically-conductive adhesive agent and the electrode pads is small, a bonding strength between the crystal plate and the electrically-conductive adhesive agent decreases, and an impact resistance of the crystal device is reduced as well. For this reason, it is desirable to check the bonding status of the crystal plate and the electrically-conductive adhesive agent.
The published application JP 2010-161528, for example, discloses a piezoelectric substrate including a mount electrode section for checking the bonding status of the electrically-conductive adhesive agent. The published application JP 2010-161528 discloses that the piezoelectric substrate includes an exposure section, which is formed in the mount electrode section to expose the piezoelectric substrate, and the electrically-conductive adhesive agent that is spread and bonds to the piezoelectric substrate, and can be inspected through the exposure section.